а) 0,5 + 0,75 = 1/2 + 3/4 = (2/4) + (3/4) = 5/4 = 1,25б) 2,5 - 0,7 = 5/2 - 7/10 = (25/10) - (7/10) = 18/10 = 1,8в) 0,4 × 0,625 = 4/10 × 625/1000 = 2500/10000 = 1/4 = 0,25г) 1,2 ÷ 1,08 = 12/10 ÷ 108/100 = 12/10 ÷ 27/25 = 12/10 × 25/27 = 12/27 = 4/9 ≈ 0,44444444444444445
а) 0,5 + 0,75 = 1/2 + 3/4 = (2/4) + (3/4) = 5/4 = 1,25
б) 2,5 - 0,7 = 5/2 - 7/10 = (25/10) - (7/10) = 18/10 = 1,8
в) 0,4 × 0,625 = 4/10 × 625/1000 = 2500/10000 = 1/4 = 0,25
г) 1,2 ÷ 1,08 = 12/10 ÷ 108/100 = 12/10 ÷ 27/25 = 12/10 × 25/27 = 12/27 = 4/9 ≈ 0,44444444444444445